The head of the Canada Revenue Agency says that Canadians should expect better service this tax season on the agency’s customer service lines following a scathing report from the auditor general last year.

CRA Commissioner Bob Hamilton appeared Tuesday before the Senate’s finance committee, and faced some tough questions about what, exactly, has been done since Auditor General Michael Ferguson revealed that only a third of calls to the CRA’s help-line were getting through.

“Since (the report), we believe that we’re getting to a point where about half the calls are getting through,” Hamilton said.

“I’m not trying to say that’s perfect, but it’s an improvement.”

WATCH: CRA 30% error rate could impact Canadians’ taxes, says auditor general

The CRA has also hired more staff to work the lines, and is offering more “self-serve” options on the automated voice system to handle callers who have basic questions.

In addition, Hamilton added, the system now presents callers with a busy signal only when the queue is full and the wait time is more than five minutes. The previous standard was two minutes.

A tax deadline of April 31?

Ferguson’s report, tabled last November, also laid bare the quality-control issues at the CRA’s call centres. The auditor found that Canadians were being given incorrect information 29 per cent of the time, leading to errors in their tax returns.

Questions specifically about filing personal taxes got an even higher error rate, 36 per cent.

That is unacceptably high, Hamilton acknowledged, and the CRA has since implemented a new approach to training its staff.

It builds on the previous six-week standard training program, he explained, adding more “support and coaching” for call-centre workers through their first three to 10 weeks working the lines.

In order to progress to more complex calls, they must now pass through a series of training “gates.”

At the same time, a national CRA team has started making “blind calls” to the help-line to anonymously test the accuracy of responses since these changes were made, the senators heard.

Hamilton revealed that the CRA is using the exact same test questions used by the auditor general to measure the agency’s accuracy (by calling the help-line and pretending to be a tax filer). Some were relatively complicated, but others were as basic as “when is the tax-filing deadline?”

“One of the responses that came back (to the auditor) was April 31,” Hamilton told the senators. “There is no April 31.”

It’s possible CRA staffers became confused, the commissioner said, because the agency can change the filing deadline from one year to the next. But that’s no excuse, he added.

Conservative Sen. Nicole Eaton seemed to agree.

“If you don’t understand Canada’s tax code, how can you expect Canadians to?” she said. “I mean, really.”

Eaton was also unimpressed by some of the explanations around how training standards have been improved, calling them “so much blah blah.”

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With tax season in progress, the senator said, small business owners, in particular, may have complex questions about the new tax regulations linked to Canadian-Controlled Private Corporations.

“Training enhancements are in progress. That means nothing to me. What exactly does it mean? How many more hours? What standards of education are you demanding from people who answer calls and give Canadians the answers?”

Hamilton said he would provide the committee with a written rundown answering those questions.

“Let me assure you that the staff that work at our call centres across the country … are committed to implementing this plan,” he noted. “I’m very proud of the work that CRA’s employees do.”

The 2016 federal budget allocated $50 million over four years for the CRA to improve its services. The phone system is also long overdue for an upgrade, Hamilton noted on Tuesday, because it still doesn’t allow the agency to record calls for quality assurance or even to give callers an estimated wait time.

The agency is working with Shared Services Canada (the government’s central IT department) to modernize the phone line.